What to eat during your first trimester

You are not “eating for two.” Not yet. In the first trimester, your energy needs usually don’t rise at all, but your micronutrient demands do. This is why the smartest approach is density over volume. Build small, frequent meals around the nutrients that matter most early on—then layer in simple tactics that tame nausea and keep food safety tight.

The result is a calm system that supports neural tube formation, early organ development, and steady maternal energy. Think of it as a compact nutrition stack designed for the most volatile 12 weeks.

Start with folate. The neural tube closes by about week four, often before you even feel pregnant. That is why experts advise a prenatal vitamin with at least 400 micrograms of folic acid before conception and through the first 12 weeks, alongside a diet that gets you to about 600 micrograms daily overall. If you’ve had a prior neural tube defect or certain risk factors, your clinician may recommend more; otherwise, a standard prenatal plus folate-rich foods does the job.

Hold the calories steady. With one fetus, the first trimester typically requires no extra calories. Focus on quality rather than quantity now; the additional 340 to 450 calories kick in later in pregnancy. That frees you to spend your appetite budget on nutrient-dense foods you can tolerate when morning sickness is loud and appetite is quiet.

Keep iron in play. Blood volume starts ramping up early, and iron carries oxygen to both you and the embryo. Many prenatal vitamins supply iron, and food helps you absorb it better. Pair a small portion of beef, chicken, or tofu with vitamin-C-rich produce like oranges, kiwi, or bell peppers to boost absorption. The research base supports daily iron in pregnancy to reduce anemia risk; speak with your clinician if supplements aggravate nausea, as timing and formulation can be adjusted.

Do not skip iodine. Iodine supports thyroid hormones, which drive brain and nervous system development. The RDA in pregnancy is 220 micrograms a day, and many authorities recommend a prenatal that specifically includes about 150 micrograms as potassium iodide because some prenatals still omit iodine. Use iodized salt in cooking and include eggs, dairy, and lower-mercury fish to round things out.

Add choline with intent. Choline is a quiet powerhouse for fetal brain development and methylation. Aim for roughly 450 milligrams a day. Eggs are the easiest delivery system; one or two a day covers a big portion of your target. Many prenatals lack meaningful choline, which is why diet matters here. If you are egg-averse, pivot to lean meats, soy foods, or dairy and discuss a choline add-on with your clinician.

Keep vitamin D and calcium consistent. Your bones and your baby’s skeleton both need steady inputs. Most prenatals include vitamin D, and the RDA in pregnancy is 600 IU (15 micrograms) daily. Calcium needs are generally 1,000 milligrams a day from food and supplements combined. If a blood test shows low vitamin D, your provider may temporarily increase the dose.

Build in DHA from seafood or supplements. DHA, the omega-3 fatty acid found in fish, supports brain and eye development. Two modest seafood meals a week is the simplest way to cover your bases, but if fish is off the table during the first trimester, talk to your provider about a DHA supplement. Current federal guidance emphasizes 8 to 12 ounces a week of lower-mercury seafood for those who are pregnant or breastfeeding. Canned light tuna, salmon, sardines, tilapia, and trout are reliable options.

Now solve for nausea. The first trimester is famous for it, but you can engineer around it. Small, frequent meals beat large plates. Keep dry, bland carbs handy and layer in a bite of protein each time—half a banana with a spoonful of yogurt, a plain cracker chased by a few almonds, or toast topped with scrambled egg. Clinical guidance supports vitamin B6 as a first-line option; your clinician may pair it with doxylamine if needed. Ginger tea or chews help some people. Stay ahead of dehydration with sips of water or diluted juice.

Be exact about caffeine and alcohol. The simplest rule set: hold caffeine to under 200 milligrams a day and avoid alcohol altogether. That translates to roughly one 12-ounce cup of brewed coffee, remembering that tea, sodas, and chocolate also contain caffeine. There is no known safe amount or timing for alcohol in pregnancy, so skipping it is the protective choice.

Practice food safety like it is part of prenatal care. Listeria risk climbs in pregnancy, and early infection can be serious. Avoid unheated deli meats and hot dogs unless you reheat them until steaming. Choose pasteurized dairy only. Wash produce thoroughly and keep your fridge at or below 4°C/40°F. For seafood, stick with the lower-mercury list and skip high-mercury species like shark, swordfish, king mackerel, and tilefish. If you love tuna, prefer canned light over albacore during pregnancy.

If you’re plant-forward or fully vegetarian, plan two details. First, choline: eggs make it easy; without eggs, consciously add soy foods and dairy and ask about a choline supplement if your intake is low. Second, vitamin B12: it isn’t naturally present in plant foods, so use fortified foods or a supplement to hit the 2.6 microgram RDA in pregnancy. Iron from plants is less bioavailable, so pair beans, lentils, and leafy greens with vitamin-C-rich fruits and vegetables to lift absorption.

Here’s how a calm, nausea-aware day of eating might look in real life. Wake up and take your prenatal with a small snack to cut queasiness from an empty stomach. A slice of toast with peanut butter works when nothing else will. When you can, swap to breakfast with an egg and some fruit. That single egg brings choline and iodine, while the fruit adds vitamin C to help iron absorption at later meals. Mid-morning, sip ginger tea and nibble a few whole-grain crackers. If you tolerate yogurt, go for a small cup; dairy adds iodine and calcium, and the protein steadies blood sugar.

Lunch should be compact and simple. A small bowl of fortified whole-grain cereal with milk plus a side of berries is fine on a rough day. On better days, try a warm rice bowl with sautéed salmon, spinach, and sesame seeds. The salmon brings DHA, the greens bring folate, and warm, savory food is often easier than cold salads during the first trimester. If fish is a hard no right now, sub tofu and add a drizzle of canola or olive oil for healthy fats.

The afternoon can be the danger zone for nausea. Keep your stomach from going completely empty. Half a banana, a few almonds, or a small grilled-cheese on whole-grain bread can be enough. If you are commuting, pack shelf-stable options: roasted chickpeas, whole-grain crackers, or an applesauce pouch. Keep water within reach and take regular sips; dehydration makes everything worse.

Dinner doesn’t need to be elaborate. If you eat meat, a palm-sized portion of chicken with mashed sweet potatoes and steamed broccoli delivers iron, beta-carotene, vitamin C, and fiber in a soft, gentle format. If you eat fish, swap the chicken for baked trout or canned light tuna mixed into a warm pasta with peas and lemon. If you are vegetarian, aim for a lentil-tomato stew with a dollop of yogurt. Finish with a kiwi or orange segment for vitamin C. If heartburn creeps in, keep dinner earlier and smaller, and sleep with your upper body slightly elevated.

When nothing sounds good, rely on the rule of twos: two bites every two hours. You can accumulate a full day’s nutrition in small increments. Use fortified foods to your advantage: whole-grain cereals with added folic acid, plant milks fortified with B12, and breads made with enriched flour. Many people find cold foods easier; smoothies built with yogurt, fruit, and oats can be a gentle vehicle for micronutrients. On the worst days, give yourself permission to coast with bland staples, then rebound the next day.

Two more levers matter. First, salt-choice. If you cook at home, iodized salt is the simplest insurance policy for iodine status, especially if your prenatal does not include it. Second, sunlight and checks. Vitamin D status varies by geography and skin tone; if your provider tests and finds you’re low, short-term supplementation is common and safe in pregnancy.

All of this adds up to a modest framework for what to eat in the first trimester of pregnancy: fewer large meals, more nutrient-dense, nausea-tolerant mini-meals, and disciplined food safety. Keep the caffeine sane, skip the alcohol, and favor fish that are low in mercury. Use your prenatal vitamin as a foundation, then design your plate to deliver folate, iron, iodine, choline, vitamin D, calcium, and DHA. It is a calm, repeatable routine for unstable weeks—and it prepares you for the higher-calorie demands that follow in the second and third trimesters.

If nausea becomes severe or you’re losing weight, contact your clinician promptly; there are safe, evidence-based medications when diet alone isn’t enough. If you have a thyroid condition, vegan diet, or prior neural tube defect, ask for personalized guidance on iodine, B12, and folate dosing. Your first trimester nutrition doesn’t need to be perfect. It needs to be steady, strategic, and safe.